索氏抽提测定含油量的方法改良及其应用

摘要

对索氏抽提法测定含油量的方法进行了改良,在原索氏抽提装置上加装了恒温冷凝水系统,将冷凝水温度改为恒温15℃.改良后的索氏抽提法与原方法相比,测定结果的准确度和灵敏度显著提高,有效消除了因季节、气候等因素引起的温度变化所带来的测定值差异.2007年至2010年加拿大谷物委员会组织36家国际权威油料检测实验室开展国际油料品质比对检测.结果显示,本实验室检测结果|Z|值均小于2,且采用改良索氏抽提法后,测定结果的Z比分数由-1.98～-0.12减小到-0.60～0.20,相对偏差由-2.5％～-0.38％减小到-1.24％ ～0.24％,实现了含油量检测结果的国际接轨.%Soxhlet extraction method was modified for determination of oil content with combination of condensaternwater system at constant temperature. The optimal temperature of condensate water was at 15 °C constantly. Modified method showed significant improvement on accuracy and sensitivity, and has less discrepancy in different seasons and surrounding temperatures. From 2007 to 2010, according to the International Laboratory Comparison on Determination of Oilseed, results of modified soxhlet extraction method illustrated excellent consistency with the other 35 international authoritative oil testing laboratories, and showed that the ∣Z∣ values were less than 2. Additionally, with the modified soxhlet extraction method, Z values decreased from - 1. 98--0. 12 to -0. 60 ~0. 20, and relative deviationrndecreased from -2.5%--0.38% to -1.24% -0.24% , which suggedted that these test results of modified method reached international standards.